Mine cage safety device



Feb. 16, 1960 C, E, CHANDLER 2,925,151

MINE CAGE SAFETY DEVICE Filed July 25. .954 4 Sheets-Sheet l W Q; ff

' a BY Feb. 16, 1960 c. E. CHANDLER 2,925,151

MINE CAGE SAFETY DEVICE Filed July 26, 1954 4 Sheets-Sheet 2 Feb. 16,1960 Filed July 26, 1954 C. E. CHANDLER MINE CAGE SAFETY DEVICE 4Sheets-Sheet 3 Feb. 16, 1960 c. E. CHANDLER MINE CAGE SAFETY DEVICEFiled July 26. 1954 4 Sheets-Sheet 4 United States Patent O MINE CAGESAFETY DEVICE Clifford E. Chandler, Hayden Lake, Idaho Application July26, 1954, Serial No. 445,754

1 Claim. (Cl. 18'7-8'5) and it would drop to the bottom of the shaft,killing the` passengers.

It is the principal purpose of my invention to provide asafety device onthe cage which will operate to support the cage in the shaft if thesupporting cable should break or become slack.

A further purpose of my invention is to provide such a device havingmeans to stop the cage automatically in the event that the supportingcable should part .or become slack. Manual operating means are alsocontemplated which may be manipulated by a passenger to stop the cagewhen desired.

My improved safety device comprises a pair of guide and brake shoesattached to the cage and in sliding Aer1- gagement with the guidemembers in the shaft. Means on the cage are provided to force the shoesout against the guides with sufficient pressure to stop the cage uponremoval of tension on the supporting cable which suspends the cage fromthe operating crane or winch. These means include brake levers adjacentthe shoes and an hydraulic piston and cylinder adapted to operate thelevers. The supporting cable is mounted on a spring loaded lever so thatwhen the cable supportsthe weight of the cage, the spring is held inconnection. When the tension -is removed from the supportting cable, thespring is released and expands, causing the cable mounting lever tooperate a valve connected to the hydraulic cylinder. cylinder and itspiston is forced down, operating the braking levers to force the shoesagainst the guide members in the shaft.

The nature and advantage of my invention will appear more fully from thefollowing description and the accompanying drawings. The description anddrawings are considered illustrative only, however, and are not intendedto limit the invention except insofar as itis limited by the claim.

In the drawings: 4

Figure 1 is a view in side elevation of a mine cage equipped with myimproved device;

Figure 2 is a plan sectional view taken substantially on the line 2-2 ofFigure l;

Figure 3 is a sectional view taken on the line 3-3 of Figure 2;

Figure 4 is a view similar to Figure 3, but showing the safety device inposition to support the cage between the guide members;

When the Valve is opened, air is admitted to the' "ice Figure 5 is anenlarged sectional view taken on the line 5-5 of Figure 1;

Figure 6 is an enlarged sectional view taken on the line 6`6 of Figure3; and

Figure 7 is an enlarged sectional view taken on the line 7-7 of Figure3.

Referring now to the drawings and to Figures 1 and 2 in particular, myimproved safety device is shown as being used on a mine cage generallyindicated by the numeral 10. The cage 10 has a passenger platform 11which is enclosed on `all sides by lattice sides 12. .A door (not shown)is included in one side 12 to admit passengers to the cage 10. Above thepassenger compartment by the platform lil and the sides 12, a supportingframe is provided. The supporti-ng frame comprises two side plates 13and 14 which have end frames 15, and 16 attached thereto. The members13, 14, 15 and 16 form a rectangular frame which supports the sides 12and the platform 11. A sloped roof member 17 is attached to the platesI13 and 14 to protect the cage and its occupants from falling objects.Stationary guide shoes 18 and 19 are provided on the cage 10 at thelower edge tocooperate with wooden guides 20 `and 21 positioned. withinthe shaft to guide the cage smoothly up and down the shaft. Additionalguide shoes 22 and 23 are providedon the cage 10 at its upper end.Theguide shoes 22 and 23 are mounted on springsteel straps 24 and 25which extend downwardly beside the cage 10 and are secured at the loweredge. With this con-, struction, the upper shoes 22 and 23 maybe movedoutwardly against the guides 20 and 21 by bending the steel straps 24and 2 5. The straps, however, normally hold the Shoes 22 and 23 againstthe plates 13 and 14,.` Two main supporting members 2 6 and 27 aremounted between the plates 13 and 14. The members 26 and 27 havevertical flanges 28 which are riveted to the plates 13 and 14 to securethe members 26 and 27 in place. A cable mounting lever 29 is positionedbetween the members 26 and 27 near their upper edges. The lever 29mounts a supporting cable 30 which extends upwardly to a crane boom (notshown) to support the cage 10. rIhe lever 29 has a vertical slot 31therein which receives a bolt 32 fixed between the members 26 and 27.Links 33 and 34, also positioned between the members 26 and 27, arepivoted to the lever 29 and extend outwardly. The outer ends of thelinks 33 and 34 have slots 35 and 36 therein which receive bolts 37 and33. The bolts 37 and 38, like the bolt 32, are xed between 'the members26 and 27. With the construction just described, the lever 29 is free tomove up and down between the members 26 and 27 for the length of theslot 31. The slots 35 and 36 inthe links 33'and 34 are so positionedthat when the lever 29 is moved up until the bolt 32 rests in the bottomof tthe slot j31, the bolts 37 and 3S also rest in the outer ends of theslots 35 and 36. When the cage 10 is suspended by the cable 30, thelever 29 and links 33 and 34 are drawn up as just described, and asshown in Figure 3, so that the weight of the cage is carried by thebolts 32, 37 and 38.

At the lower edge of the lever 29, a vertical rod 39 is fixed. The rod39 extends downwardly between `the members 26 and 27 through a cross bar40, which is secured between the members 26 and 27. t A spring 41 ispositioned around the `rod 39 below the cross bar 40. A washer 42 and anut 43 on the rod 39 secure the spring 41 in place. The spring 41 is somounted that when the lever 29 is drawn up so that the bolt 32 rests inthe bottom of the slot 31, the spring 41 is compressed. Then whentension is removed from the cable 30, the spring 41 expands and drawsthe lever downward. The. supporting members 26 and 27 have apertures 44therein adjacent the spring 41 to allow sufficient clearance for thesprin 41 to operate freely. The cross bar 40 seats atutlteutpV of theapertures 44.

Also mounted between the supporting members 26 and 2,7 'are` fourL-shaped braking levers 45, 46, 47 and 48. Ther braking levers 45 uand46 "are, positioned near the upper` edges lof members 26 and 27 andoutwardly from th'espring 41. 4The braking levers 47 and 48 arepositioned near the lower edges of the members 26 and 27, the" lever 47being below the lever 4S and the lever 48 being below the lever-46. Thelevers 45 and 46 are pivotally suspended between the members 26 and 27by pivot pins 49'aud 50 as shown in Figures 2 and 3. The levers 45 and46 have horizontal portions 45a and 46a which extend inwardly and havevertical portions 45h and 46b which depend from the pivots 49 and 50.The braking levers 47 and 48 are pivotally suspended -between themembers26 and 27 by pivot pins 51 and 52 similar to theV levers 45 and46 and have like horizontal portions 47a and 48a and like verticalportions 4'bv and 48b. The free ends of the portions 47a and 48a overlapeach other as best shown in Figure 7. The ends of the portions 47a and48a are offset somewhat to each side so that there is aspace betweenthem. Positioned between the free ends of the portions 47a and 48a is apiston rod 53. A pin 54 extends through the rod 53 and through slots 55and 56 formed in the offset ends of the portions 47a1 and 48a. The rod53 connects to a piston 55 within an hydraulic cylinder 56 which ispositioned between the members 26 and 27 labove the levers 47 and 48.

With the construction just described, the admittance of lipid underpressure to thje hydraulic cylinder 56 will cause the piston 55 andpiston rod 53 to be forced down- Ward, Vthus moving thehorizontalportions 47afvand 48a of the braking levers 47 and 48 downward. Thisaction, of course, 'pivots the levers 47 and 48 about the pins 51 and 52and moves the depending portions 47b and 48h outwardly. In order toactuate the upper brakinglevers 45 and 46 in the same manner, Atie rods57 and 58, best shown in Figures 3, 4 and 6, 'are provided between theseveral levers 45, 46, 47 and 48. The tie rod 57 has yokes 59 and 60at'each end. The lower yoke 59 pivotally connects the tie rod to thehorizontal portion 47a of the lever 47 intermediate the slot 55 and thepivot 51. The upper Vyoke 60 pivotally connects the tie rod 57 to thefe'e 'end of the horizontal portion 45al of the lever 45. The tie rod 58has a lower yoke 61 and an upper yoke 62 which connect it to the levers46 and 48 in a similar manner. Thus, the downward movement of theportions 47a and 48d cause a downward movement of the portions 45uV and46a and causethe braking levers 45 and 46 to pivotand swing theirvertical portion 45b and'46b outwardly. rIhe side plates 1 3 and 14 havecut out portions 63 therein adjacent the levers `45, 46, 47 and 48 toallow the vertical portion 45a, 46a, 47b and 48bto pass through. Uponmoving outwardly, the lever portions 45b and 47b contactthe steel strap24 supporting the shoe 22 and force it outwardly, pressing the shoe 22against the guide 20. The lever portions 4617 and 4,8b contact the strapsupporting the Vshoe 23 and force it outwardly, pressing the shoe 23against the guide 21. Sufficient pressure is 'supplied to the cylinder56 to apply enough friction force to the shoes 22 and 23 to stop theVcage 10 and support it in the shaft. Figure 4 shows the mechanism inthis Positiva 'In order to supply fluid to the cylinder 56, an inletpipe 64 is provided. The pipe 64 connects the cylinder 56 to a'pressuretank'65 mounted on the supporting member 26. A pressure valve 66 ispositioned in the pipe 64 to control the fluid flow. A control` handle67 is included on the valve 66 and extends inwardly through a slot inthe member 26 to the space between the members 276 and 27. A flexibleconnector 68 is attached to the control handle 67 and connects it to thewasher 43 which restrains the porting cable 30, the connector 68 holdsthe valve handle 67 in the closed position. A spring'69 connected to themember 26 opposes the forc'e of the connector 68, so that when thespring 41 expands due to removal of tenf sion on the cable 30, theVconnector 68 is slackened as shown in Figure 3 and the spring 69 pullsthe valve handle 68 down to the open position, thus admitting fluid tothe cylinder 56.

An outlet pipe 70 also is connected to the cylinder 56,

`and has a pressure valve 71 thereon. The valve 71 is manually operatedby a lever 72 which extends down into the passenger compartment of thecage 10. By manually operating the valve 71, the occupants of the cage10 may relieve the pressure in the cylinder 56. Since there is apossibility of mechanical failure in the automatic valve openingmechanism made of the parts 66, 67, 68 a'rid69, a second inlet pipe 73is included from the cylinder 56 to the tank 65. The pipe 73 bypassesthe valve 67, that is,

it is in parallel with the pipe 64. A Valve 74 is included in the pipe73 -to control -uid flow therein. The valve 74 has a manual controlhandle 75 which extends into the passenger compartment. The valve 74 isspring loaded l in the closed position, but by manipulating the handle75,`

spring 41.` The connector 6.8 is of such a length that when the Series41 is @repressed by the tension Qf the Supit may be opened to admitfluid to the cylinder 56. With this construction, occupants of the cage10 `may manually brake the cage 10 if the valve 66 fails to operate,

VIn order to insure that the shoes 22 and 23 are' drawn away from theguides 20 and21 when the safety device is notoperating, springs 76and 77are provided, which hold the Vshoes back against the side plates 13 and14. Figure 5 shows this construction best. The springs 76 and 77areconnected to bolts 78 and 79 which extend through enlarged apertures inthe flanges 28 of the supports 26 and 27 and through apertures in the.plates 13 and 14.

The bolts 78 are fixed to ears 80 on the shoe 22 and the bolts 79 arefixed to ears 81 on the shoe 23. When the shoes 22 and 23 are forcedoutwardly, the springs V76 and 77 are tensioned. `When the shoes '22 and23 are released, the springs 76 and 77 return them to their normalposition, and consequently force the levers 45, 46, 47 Vand, 48 to theirnormal positions.

The operation of my invention is entirely automatic and is, therefore,particularly useful in mine cages of the present type. It is notnecessary to depend upon quick thinking of the occupants to stop thecage if breakage should occur. At the Vinstant the supporting cablecease 'to support the weight of the cage 10, the cable mounting lever279 is forced downwardly by the spring 41. This action allows the valve66 to open and admit Huid to the cylinder 56. Immediately the` levers45, 46, 47 and 48 operate to force the shoes 2,2 and 23 out against theguide members 20 ,and 21. Of course it is necessary that the pressuretank 65 be maintained at suflicent pressure to operate the deviceproperly, so the tank must be'checked frequently and replaced when thepressure drops below a specifedvalue. Y

The paralleled emergency valve 74 and the exhaust valve 71 also performa unique function. ln the event of a cable break which leaves the cagesuspended in the shaft, it Vis often desirable that the occupantsYleave'the cage so that while a new cable is being attached, .there is nodanger to them. In the event that the cage is left suspended betweenlevels, the occupants can manipulate -the valves 71 and 74 to lower thecage to the nearest elevator cage, a safety device for halting andsupporting the cage in the shaft comprising a pair of guide shoes on thecage, said shoes being in sliding engagement with said guide members inthe shaft, said cage including a supporting frame between the shoes,shoe supporting means xed to the frame below the shoes and supportingthe shoes for limited transverse movement, braking levers mounted on theframe adjacent the shoes, said braking levers operable to force theshoes outwardly against the guide members, an hydraulic cylinder mountedon the frame, a piston Within the cylinder and having a rod extendingtherefrom, said rod being connected to the braking levers to move themagainst the shoes upon introduction of fluid to the cylinder, areservoir tank containing uid under pressure, said tank having a iluidpipe extending therefrom to the hydraulic cylinder, a control valve inthe pipe, and means connecting the valve to the cable to open the valveupon removal of tension from the elevator supporting cable, said meanscomprising a cable mounting lever attached to the supporting cable,

a slot in the lever, a bolt extending through the slot and beingattached to the supporting frame, spring means on the lever opposing theforce exerted by the supporting cable and operable to move the lever on'the bolt upon y Ratei-ences Cited in the file of this patent UNITEDSTATES PATENTS 583,125 Rossler May 25, 1897 956,707 Hyde May 3, 19101,015,137 Clark Jan. 16, 1912 1,032,710 Sivel July 16, 1912 2,545,457Gammell Mar. 20, 1951 FOREIGN PATENTS 123,732 Germany Sept. 11, 1901

